Struct SdfGrid 

pub struct SdfGrid {
    pub nx: usize,
    pub ny: usize,
    pub nz: usize,
    pub dx: f64,
    pub origin: [f64; 3],
    pub values: Vec<f64>,
}

A 3-D signed distance field stored on a uniform Cartesian grid.

Fields

nx: usize

Number of cells in the x direction.

ny: usize

Number of cells in the y direction.

nz: usize

Number of cells in the z direction.

dx: f64

Uniform cell spacing (same in all directions).

origin: [f64; 3]

World-space coordinate of the (0,0,0) grid corner.

values: Vec<f64>

Flat storage: index = i*ny*nz + j*nz + k.

Implementations

impl SdfGrid

pub fn new(nx: usize, ny: usize, nz: usize, dx: f64, origin: [f64; 3]) -> Self

Create a new grid filled with f64::MAX.

pub fn index(&self, i: usize, j: usize, k: usize) -> usize

Flat index for cell (i, j, k).

pub fn world_pos(&self, i: usize, j: usize, k: usize) -> [f64; 3]

World-space centre of cell (i, j, k).

pub fn get(&self, i: usize, j: usize, k: usize) -> f64

Read the SDF value at (i, j, k).

pub fn set(&mut self, i: usize, j: usize, k: usize, v: f64)

Write the SDF value at (i, j, k).

pub fn compute_sphere_sdf(&mut self, center: [f64; 3], radius: f64)

Fill the grid with the signed distance to a sphere.

pub fn compute_box_sdf(&mut self, box_center: [f64; 3], half_extents: [f64; 3])

Fill the grid with the signed distance to an axis-aligned box.

pub fn compute_cylinder_sdf( &mut self, center: [f64; 2], radius: f64, half_height: f64, )

Fill the grid with the signed distance to an infinite cylinder aligned along the z-axis.

pub fn compute_torus_sdf( &mut self, center: [f64; 3], major_radius: f64, minor_radius: f64, )

Fill the grid with the signed distance to a torus centred at the origin in the xz-plane.

pub fn gradient_at(&self, i: usize, j: usize, k: usize) -> [f64; 3]

Estimate the gradient of the SDF at (i, j, k) using central differences.

pub fn total_cells(&self) -> usize

Total number of cells in the grid.

pub fn sample(&self, pos: [f64; 3]) -> Option<f64>

Trilinear interpolation of the SDF at an arbitrary world-space point.

Returns None if the point is outside the grid.

pub fn gradient_at_point(&self, pos: [f64; 3]) -> Option<[f64; 3]>

Compute the gradient at an arbitrary point using trilinear interpolation of gradient values.